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31.
The liver is distinguished from other tissues by (a) its detoxifying function, (b) its resistance to apoptosis, and (c) its regenerative response to damage. Hepatocellular carcinoma arises when chronic insults, such as hepatitis or iron overload, constitutively activate this regenerative program. Here, we propose that the proliferative response of the liver to damage underlies the resistance of hepatocellular carcinoma to cytotoxic therapy, and that hepatocellular carcinoma growth should therefore be more readily controlled by using a networked combination of noncytotoxic interventions to interrupt the damage-inducible regenerative pathway. To this end, hepatocellular carcinoma boasts a wealth of potential drug targets, including viral replication, the antiapoptotic immunosuppressant alpha-fetoprotein, hepatic iron overload, inflammatory signaling, extracellular proteases, and growth factors. By blocking these positive feedback loops in parallel, and so returning the host environment to a more normal state, epigenetic repression of tumor-suppressor gene function may be reversed and tumor dormancy restored. Noncytotoxic maneuvers that short circuit damage resistance loops may thus represent an indirect form of gene therapy meriting incorporation into hepatocellular carcinoma clinical trials. 相似文献
32.
Marcaine applied to irritated nerve roots during extradural spinal surgery may attenuate sympathetically mediated and somatosensory (pain)-related hypertensive and tachycardic crises. 相似文献
33.
34.
B J Gainor R G Epstein J E Henstorf S Olson 《Clinical orthopaedics and related research》1988,(230):207-213
Thirty-five feet in 21 patients, who had had metatarsal head resection for painful rheumatoid forefoot deformities, were analyzed retrospectively. All patients but one were allowed to ambulate 48 hours after surgery. The follow-up period averaged 29 months. A grading system was devised to assess the clinical results based upon pain relief, capacity to ambulate, shoe wear, cosmesis, and use of walking aids. Using this system, the results were 46% excellent, 34% good, 17% fair, and 3% poor. One patient developed a superficial wound infection, which healed uneventfully. Bony impingement was observed on follow-up roentgenograms of 67% of the resectional arthroplasties. This finding was generally asymptomatic, and it did not correlate with the clinical outcome. Smooth wire fixation was used in some of the feet, but it did not improve the results either roentgenographically or clinically. 相似文献
35.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
36.
Proteins were extracted from corneocytes of skin of 2-day-old rats and fractionated by gel filtration and cation exchange column chromatography. The different protein fractions were tested for direct inactivation of herpes simplex virus infectivity as determined by reduction of plaque formation. The most effective protein fractions against herpes simplex virus were a neutral pH buffer soluble and mol. wts. ranging from 20 K to 30 K. Amino acid composition of the proteins were virtually identical to epidermal histidine-rich proteins. The activity was significantly (P less than 0.001) stronger against type-2 than type-1. The activity was most stable at pH 7.2 and the rate of inhibition increased in a time-dependent manner up to 4 h. The 50% effective dose was estimated as 1.1 micrograms protein/ml. 相似文献
37.
38.
Y. F. He P. D. Ross J. W. Davis R. S. Epstein J. M. Vogel R. D. Wasnich 《Calcified tissue international》1994,55(4):243-248
We calculated how long to wait before repeating bone mineral density (BMD) measurements to reassess fracture risk. Correlation results from serial measurements of 495 postmenopausal Japanese-American women were used to estimate 95% confidence intervals (CI) for future BMD. After 7 years of follow-up, BMD correlations with the initial measurement ranged between 0.81 and 0.94, depending on age group and measurement site. In this analysis, the period between measurements was defined as the time required for the lower 95% CI to fall below the BMD value corresponding to doubling of fracture risk. Progressive bone loss causes fracture risk to double after 10 years, on average. However, the 95% CIs indicate that a second BMD measurement will detect risk doubling after only 2 or 3 years for some women. For untreated, early postmenopausal women, the period between measurements was approximately 2–5 years for the radius and 4–6 years for the calcaneus, depending on the initial BMD level. The period was approximately 1 year longer for women age 60 and older. Treatments that halve the bone loss rate would increase the period by 1–3 years. In the absence of a second measurement of BMD, the CI will continue to expand with time, corresponding to a wider range in risk between individuals, and a greater proportion of women will be at increased fracture risk. Obtaining a second BMD measurement pinpoints the patient's status within the precision of the measurement. We conclude that repeated BMD measurements will provide a more accurate estimate of fracture risk than a single, baseline measurement. 相似文献
39.
Heterotopic heart transplantation: a radiographic review 总被引:1,自引:0,他引:1
C K Adey P H Nath B Soto M S Shin M Schwartz A E Epstein J K Kirklin 《Radiographics》1987,7(1):151-160
Heterotopic heart transplantation can be performed in the presence of high pulmonary vascular resistance. The authors call attention to a rare, but potentially life-saving procedure. 相似文献
40.
Primary epithelial tumors of the bladder are extremely rare in children and adolescents. We report a case of transitional cell carcinoma in an adolescent with Turner's syndrome. The patient presented with intermittent gross hematuria and mild dysuria. A mass was identified on the trigone of the bladder near the left ureteral orifice, and histological evaluation revealed grade II to III in situ papillary transitional cell carcinoma with foci of submucosal invasion. Transurethral resection of the tumor was performed, and the patient remains free of disease 2 1/2 years later. The literature on transitional cell carcinoma of the bladder in children is reviewed. 相似文献